The invention discloses a window opening and closing adjuster. The window opening and closing adjuster comprises a box body; a cavity is fixedly formed in the box body; the upper end wall of the cavity is rotationally provided with a main rod and side rods arranged in bilateral symmetry; the lower end wall of the cavity isprovided with a transmission cavity; the lower end wall of the transmissioncavity is provided with a sliding cavity; the main rod rotationally penetrates through the cavity and is connected with the lower end wall of the sliding cavity in a sliding fit mode; the side rods rotationally penetrate through the cavity and are connected with the lower end wall of the transmission cavity in a rotating fit mode; the outer surface of the main rod is fixedly provided with a main window located in the cavity, a main wheel located in the transmission cavity, and a transmission wheel located in the sliding cavity; and the outer surfaces of the side rods are provided with a side window located in the cavity, and a side wheel located in the transmission cavity. The window opening and closing adjuster is simple in structure and convenient to use, an automatic mode is adopted bythe adjuster for achieving high-efficiency opening and closing of a window, window opening and closing adjustment is achieved through a flexible adjustment mechanism, and the diversity and safety level of the window are improved.